Abstract

Studies on flowering, pollen, pod and seed characters, germination rate and seed set percentage were
carried out on twenty five accessions of African Yam Bean (AYB). Self compatibility tests confirmed all
the accessions as obligate selfers, while the reciprocal crosses were not successful. Germination rate,
percentage seed set and pollen fertility were observed to be high in the accessions. Correlation
analysis among the reproductive traits revealed that pod length, pod width, number of locules per pod
and number of seeds per pod contributed significantly to the percentage seed set in all the accessions.
Pollen fertility and seed viability were also observed to be high in all the accessions except in TSs23
where low pollen fertility, low seed viability and low percentage seed set were recorded. All the
accessions produced tricolporate pollen grains. Pollen size ranged from 66.15 μm in TSs40 to 82.75 μm
in TSs119, pollen fertility ranged from 53.39% in TSs23 to 95.30% in TSs119, seed set ranged from
83.32% in TSs90, 89.21% in TSs23 and 95.72% in TSs3. The germination rate ranged from 59.68% in
TSs23 to 99.03% in TSs22. The percentage moisture content ranged between 4.38% in TSs22 and
11.43% in TSs119.
Key words: Pollen characters, seed set, germination rate, self compatibility.